1. Field of the Invention
The present invention relates to appliances for home or indoor gymnastics and relates more particularly to such an appliance used in exercising the arms and the legs, which can be conveniently adjusted to increase or reduce its total weight according to one's physical condition.
2. Description of the Prior Art
There are known several appliances for home or indoor gymnastics. Among the various exercising appliances dumbbell is one of the most common and economic device used in exercising the arms. Conventionally, a dumbbell is consisted of round weights joined by a short bar, by which it is lifted or swung about in the hand for muscular exercise. This structure of dumbbell has a fixed total weight once it is made. Therefore, different scale of dumbbell shall be used for different volume of training. Further, when a dumbbell drops to the floor or ground, the floor of ground may be damaged by the round weights of the dumbbell easily. There are also disclosed several adjustable dumbbells which can be adjusted to increase or reduce the total weight according to an user's physical condition. The known adjustable dumbbells are generally comprised of a short bar having a plurality of pin holes symmetrically disposed at two opposite ends for releasably fastening different pairs of round weights by lock pins. The common disadvantage of these adjustable dumbbells is that the round weights may oscillate during exercising, causing balancing problem. Another disadvantage of these adjustable dumbbells is that the pins may be broken easily causing the round weights to drop from the short bar, and therefore, exercising accident may happen easily. Further, increase the total weight of a dumbbell simultaneously increase the total size of the dumbbell to make exercising difficult.